Monthly Archives: July 2015

At our July 26th meeting we shared and discussed the upcoming Water Balloon Challenge in August. Interested kids & adults signed up and there are 5 preliminary teams creating something to launch a 2″ diameter water balloon farther than you can throw it – but there are several more rumored to be forming and folks can join in at any time.

Some of the kids afterwards viewed the drone videos from earlier in the day. You can see one of them on our Youtube channel.

Special thanks to Isaac & Matt who brought their new drone for the sharing portion of the meeting. All the kids that wanted to try it got to fly it. We also learned that one is very durable!

Preloading the Water Balloon Cannon with air pressure. Meanwhile some kids make water balloon for launching from the rubber tubing launcher on the right.One of the ‘bad’ shots where balloon busted upon launch. If you look closely at this photo you can see the water squirting out the back of the balloon in the air, apparently it was not tied tightly!

In our June meeting we discussed different water related projects and tried different water balloon launchers to learn how they worked. Besides the classic surgical tubing slingshot method of shooting water balloons that Boyd, Elise, & Jim brought, we also looked at a pressurized water cannon that Rebecca & Chris built.

The water cannon, pictured to the right, was made from 2” pvc pipe and then used a bicycle valve stem to pressurize the main chamber. By opening the 2” pvc valve after pressuring, the burst of air propelled the water balloon… well initially 40-50 feet in prototype testing. But by correcting the launch angle with the help of the other folks there, a smaller volume of water for the cushion, and increasing the pressure with the bicycle pump we discovered that it easily went into the next city block. Not sure exactly how far it will go since it was hitting tree branches down the street.

After making sure anyone that wanted to (and a few that didn’t) were drenched, we decided that this would be our next build that we could show off at the Greencastle Farmer’s Market. More details soon!